Add cache statistics

4 files changed, 64 insertions, 19 deletions

diff --git a/qtmips_machine/cache.cpp b/qtmips_machine/cache.cpp
index 753027a..acc48b1 100644
--- a/qtmips_machine/cache.cpp
+++ b/qtmips_machine/cache.cpp
@@ -2,11 +2,15 @@
 
 using namespace machine;
 
-Cache::Cache(Memory *m, const MachineConfigCache *cc) : cnf(cc) {
+Cache::Cache(Memory *m, const MachineConfigCache *cc, unsigned memory_access_penalty_r, unsigned memory_access_penalty_w) : cnf(cc) {
     mem = m;
+    access_pen_r = memory_access_penalty_r;
+    access_pen_w = memory_access_penalty_w;
     // Zero hit and miss rate
-    hitc = 0;
-    missc = 0;
+    hit_read = 0;
+    hit_write = 0;
+    miss_read = 0;
+    miss_write = 0;
     // Skip any other initialization if cache is disabled
     if (!cc->enabled())
         return;
@@ -73,11 +77,31 @@ void Cache::sync() {
 }
 
 unsigned Cache::hit() const {
-    return hitc;
+    return hit_read + hit_write;
 }
 
 unsigned Cache::miss() const {
-    return missc;
+    return miss_read + miss_write;
+}
+
+unsigned Cache::stalled_cycles() const {
+    return miss_read * (access_pen_r - 1) + miss_write * (access_pen_w - 1);
+}
+
+double Cache::speed_improvement() const {
+    unsigned comp = hit_read + hit_write + miss_read + miss_write;
+    if (comp == 0)
+        return 100.0;
+    return (double)((miss_read + hit_read) * access_pen_r + (miss_write + hit_write) * access_pen_w) \
+            / (double)(hit_write + hit_read + miss_read * access_pen_r + miss_write * access_pen_w) \
+            * 100;
+}
+
+double Cache::usage_efficiency() const {
+    unsigned comp = hit_read + hit_write + miss_read + miss_write;
+    if (comp == 0)
+        return 0.0;
+    return (double)(hit_read + hit_write) / (double)comp * 100.0;
 }
 
 void Cache::reset() {
@@ -90,11 +114,14 @@ void Cache::reset() {
             dt[as][st].valid = false;
     // Note: we don't have to zero replacement policy data as those are zeroed when first used on invalid cell
     // Zero hit and miss rate
-    hitc = 0;
-    missc = 0;
+    hit_read = 0;
+    hit_write = 0;
+    miss_read = 0;
+    miss_write = 0;
     // Trigger signals
-    emit hit_update(hitc);
-    emit miss_update(missc);
+    emit hit_update(hit());
+    emit miss_update(miss());
+    update_statistics();
     for (unsigned as = 0; as < cnf.associativity(); as++)
         for (unsigned st = 0; st < cnf.sets(); st++)
             emit cache_update(as, st, false, false, 0, 0);
@@ -157,11 +184,19 @@ void Cache::access(std::uint32_t address, std::uint32_t *data, bool write, std::
 
     // Update statistics and otherwise read from memory
     if (cd.valid) {
-        hitc++;
-        emit hit_update(hitc);
+        if (write)
+            hit_write++;
+        else
+            hit_read++;
+        emit hit_update(hit());
+        update_statistics();
     } else {
-        missc++;
-        emit miss_update(missc);
+        if (write)
+            miss_write++;
+        else
+            miss_read++;
+        emit miss_update(miss());
+        update_statistics();
         for (unsigned i = 0; i < cnf.blocks(); i++)
             cd.data[i] = mem->rword(base_address(tag, row) + (4*i));
     }
@@ -209,3 +244,7 @@ void Cache::kick(unsigned associat_indx, unsigned row) const {
 std::uint32_t Cache::base_address(std::uint32_t tag, unsigned row) const {
     return ((tag * cnf.blocks() * cnf.sets()) + (row * cnf.blocks())) << 2;
 }
+
+void Cache::update_statistics() const {
+    emit statistics_update(stalled_cycles(), speed_improvement(), usage_efficiency());
+}
diff --git a/qtmips_machine/cache.h b/qtmips_machine/cache.h
index d7bd967..6cf3a2c 100644
--- a/qtmips_machine/cache.h
+++ b/qtmips_machine/cache.h
@@ -11,7 +11,7 @@ namespace machine {
 class Cache : public MemoryAccess {
     Q_OBJECT
 public:
-    Cache(Memory *m, const MachineConfigCache *c);
+    Cache(Memory *m, const MachineConfigCache *c, unsigned memory_access_penalty_r = 1, unsigned memory_access_penalty_w = 1);
 
     void wword(std::uint32_t address, std::uint32_t value);
     std::uint32_t rword(std::uint32_t address) const;
@@ -21,6 +21,9 @@ public:
 
     unsigned hit() const; // Number of recorded hits
     unsigned miss() const; // Number of recorded misses
+    unsigned stalled_cycles() const; // Number of wasted cycles in memory waitin statistic
+    double speed_improvement() const; // Speed improvement in percents in comare with no used cache
+    double usage_efficiency() const; // Usage efficiency in percents
 
     void reset(); // Reset whole state of cache
 
@@ -29,11 +32,13 @@ public:
 signals:
     void hit_update(unsigned) const;
     void miss_update(unsigned) const;
+    void statistics_update(unsigned stalled_cycles, double speed_improv, double usage_effic) const;
     void cache_update(unsigned associat, unsigned set, bool valid, bool dirty, std::uint32_t tag, const std::uint32_t *data) const;
 
 private:
     MachineConfigCache cnf;
     Memory *mem;
+    unsigned access_pen_r, access_pen_w;
 
     struct cache_data {
         bool valid, dirty;
@@ -47,11 +52,12 @@ private:
         unsigned **lfu; // Access count
     } replc; // Data used for replacement policy
 
-    mutable unsigned hitc, missc; // Hit and miss counters
+    mutable unsigned hit_read, miss_read, hit_write, miss_write; // Hit and miss counters
 
     void access(std::uint32_t address, std::uint32_t *data, bool write, std::uint32_t value = 0) const;
     void kick(unsigned associat_indx, unsigned row) const;
     std::uint32_t base_address(std::uint32_t tag, unsigned row) const;
+    void update_statistics() const;
 };
 
 }
diff --git a/qtmips_machine/machineconfig.cpp b/qtmips_machine/machineconfig.cpp
index 13a1ff2..9329795 100644
--- a/qtmips_machine/machineconfig.cpp
+++ b/qtmips_machine/machineconfig.cpp
@@ -284,11 +284,11 @@ bool MachineConfig::memory_write_protection() const {
 }
 
 unsigned MachineConfig::memory_access_time_read() const {
-    return mem_acc_read;
+    return mem_acc_read > 1 ? mem_acc_read : 1;
 }
 
 unsigned MachineConfig::memory_access_time_write() const {
-    return mem_acc_write;
+    return mem_acc_write > 1 ? mem_acc_write : 1;
 }
 
 QString MachineConfig::elf() const {
diff --git a/qtmips_machine/qtmipsmachine.cpp b/qtmips_machine/qtmipsmachine.cpp
index 4a2b0f2..da4516a 100644
--- a/qtmips_machine/qtmipsmachine.cpp
+++ b/qtmips_machine/qtmipsmachine.cpp
@@ -13,8 +13,8 @@ QtMipsMachine::QtMipsMachine(const MachineConfig &cc) : QObject(), mcnf(&cc) {
 
     regs = new Registers();
     mem = new Memory(*mem_program_only);
-    cch_program = new Cache(mem, &cc.cache_program());
-    cch_data = new Cache(mem, &cc.cache_data());
+    cch_program = new Cache(mem, &cc.cache_program(), cc.memory_access_time_read(), cc.memory_access_time_write());
+    cch_data = new Cache(mem, &cc.cache_data(), cc.memory_access_time_read(), cc.memory_access_time_write());
 
     if (cc.pipelined())
         cr = new CorePipelined(regs, cch_program, cch_data, cc.hazard_unit());